Smoke marker arrangement



Marchz, 1967 E FQSTER [5T/M 3,311,054

l SMOKE MARKER ARRANGEMENT Filed June 2l. 1965 w m'm .Lv Um. mu m .All w mw m N w u ATTORNEYS,

United States Patent Oiice 3,31 1,054 Patented Mar. 28, 1967 3,311,054 SMOKE MARKER ARRANGEMENT John E. Foster, Timonium, and Mitchell G. Angelas,

Cockeysville, Md., assignors, by mesne assignments, to

the United States of America, as represented by the Secretary of the Army Filed June 21, 1965, Ser. No. 465,811 1 Claim. (Cl. 102-6) This invention relates to a smoke marker and more particularly to an arrangement of smoke grenades in a container whereby the burning rate is decreased and water contamination is prevented.

Smoke markers of this type are often dropped from aircraft over water and are equipped with self contained parachutes and tiring devices. They may be used to signal the location of the landing of space capsules, disabled water craft, etc., that are observed from aircraft in search thereof.

One of the problems encountered herein was the length of burning which was shortened by contamination of the marker smoke grenades Iby water entering the supporting container. Also, the grenades burnt too rapidly due to the heat generated within the flotation container.

The present invention is designed to overcome the aforesaid problems. The containers are stacked end to end, sealed with pressure sensitive tape. Each grenade is wrapped with a sheet of asbestos and the assembly is placed in a sheet metal flotation container to provide structural support therefor.

This `arrangement provides a cooler burning smoke marker since, after the first grenade is ignited, the succeeding grenade is not preignited by the heat of the preceding grenade.

A primary object of this invention is to provide a smoke marker that will burn a greater length of time.

Another object is to provide a smoke marker that is not contaminated by water.

A further object is to provide a smoke marker including a multiplicity of smoke grenades so arranged and insulated that each succeeding grenade is not preignited by the heat generated by each preceding grenade.

These and other objects and advantages of the present invention will be fully apparent from the following description when taken in connection with the annexed drawing, in which:

FIG. 1 is a side elevation, partly in section, of the smoke grenades and their arrangement;

FIG. 2 is a similar View of the complete assembly of the smoke marker, but on a smaller scale;

FIG. 3 is a sectional view taken along line 3-3 of FIG. 1 and looking in the direction of the arrows;

FIG. 4 is a detail section of the sealing means between two ofthe grenades; and

FIG. 5 is an end view looking in the direction of the arrows 5-5 of FIG. 2.

Referring in detail to the drawing, reference character 1 indicates generally, the smoke marker of this invention (see FIG. 2).

The smoke marker 1 comprises a sheet metal, cylindrical flotation container 2 which is closed at each end by lids 3 and 4, respectively. Lid 3 is provided with holes 5 and 6 (see FIG. 5). Holes 5 and 6 are for the purpose of escape of products of combustion. Lid 4 has no openings therein.

Smoke grenades (three shown) 7, 8 and 9 are arranged in abutting end to end position in container 2 and each grenade contains a smoke producing charge 10. The grenades arel provided at their ends with respective lids 11, 12, 13, 14, 15 and 16.

Each grenade is further supplied with an igniting charge 17 for initiating burning of charges 10.

Igniting charges 17 are supported in cups 18 liXed to lids 11, 13 and 15.

Lids V11, 13 and 15 are provided with smoke eXit holes 19 and lids 12 and 14 have smoke exit holes 20. Lid 16 has no smoke exit hole.

Lid 11 is provided with a nipple 21 for the attachment of a triggering device, not shown.

A spacing tube 25 (see FIG. 2) is provided at one end of the container 2 for the purpose of providing a chamber for ya parachute or like lowering means, not shown, for the smoke marker 1 when dropped from an aircraft.

As shown in FIG. 1, grenades 7, 8 and 9 are placed end to end. Sealing tape 22 is placed over holes 19 in ,lid 11, which is blown oi when grenade 7 is ignited by means, not shown.

The ends of grenades 7, 8 and 9 are sealed with pressure sensitive tape 23 and each grenade is heat insulated by wrapping it with a material such as an asbestos sheet l2-4. FIG. 4 shows a method of overlapping the ends of sheets 24 with tapes 23.

In operation, grenade 7 (the rst) is ignited by a triggering means, not shown, which initiates burning of starter mix 17 in cup 18 in lid 11. Grenade 7 then burns for `approximately two minutes. At this time grenade 8 (the second) will ignite and burn through grenade 7. The ignition of grenade 8 is caused by the exposed burning charge 10 which impinges on its starter rniX 17 in cup 18 of grenade 8. The burning process is repeated for the grenade 9 (the third), thus lasting a total of approximately 6 minutes. The asbestos wraps 24 insure a cool grenade, therefore no preignition of grenades 8 and 9 will occur. Also tapes 23 aid in containing the heat which would otherwise escape between the grenade ends and would heat container 2 which would cause preignition of succeeding grenades. Also the asbestos wraps 24 prevent increased heat in the burning process due to the confinement of the grenades 7, 8 and 9 in the container 2.

Since the marker is sealed, it will float and not become contaminated by water.

While one preferred form of the invention is shown and described, other forms of the invention are contemplated and numerous changes and modifications may be made therein without departing from the spirit of the, invention as set forth in the appended claim.

What is claimed is:

A smoke marker comprising in combination, a cylindrical container, a closure for each end of said container, there being vsmoke exit holes in one of said closures, each exit hole having a sealing tape thereon, a plurality of axially aligned smoke grenades arranged. in abutting relation within said container, each said grenade having a smoke producing charge therein, a lid closing each end of each grenade, there being smoke exit holes in all but one of said lids whereby the smoke from the burning of each succeeding grenade will exit through the preceding grenades when burned out, an igniting charge for igniting said smoke charges supported in each grenade, a sheet of heat insulating material having a width substantially equal to the length of and wrapped about each grenade, and a strip of pressure-resistant tape wrapped about the abutting ends of said grenades, its edges underlying a portion of the adjacent sheets of heat insulating material whereby heat from combustion of one grenade will be prevented from escaping from between the grenade ends to cause pre-ignition of the succeeding grenade.

References Cited by the Examiner UNITED STATES PATENTS Pain 102--37.7 Decker IGZ-37.7 Driskell 102--6 Hutchison 102--90 X Finkelstein 102-37.8

SAMUEL W. ENGLE, Primary Examiner. 

